Micro-electromechanical devices are becoming increasingly popular and normally involve the creation of devices on the μm (micron) scale utilizing semi-conductor fabrication techniques. For a recent review on micro-electromechanical devices, reference is made to the article “The Broad Sweep of Integrated Micro Systems” by S. Tom Picraux and Paul J. McWhorter published December 1998 in IEEE Spectrum at pages 24 to 33.
Many different techniques on ink jet printing and associated devices have been invented. For a survey of the field, reference is made to an article by J Moore, “Non-Impact Printing: Introduction and Historical Perspective”, Output Hard Copy Devices, Editors R Dubeck and S Sherr, pages 207-220 (1988).
Recently, a new form of ink jet printing has been developed by the present applicant, which uses micro-electromechanical technology to achieve ink drop ejection. In one form of this technology, ink is ejected from an ink ejection nozzle chamber utilising an electromechanical actuator connected to a paddle or plunger operatively positioned with respect to a nozzle chamber and which moves towards and away from an ejection nozzle of the chamber for ejecting drops of ink from the chamber.
The Applicant has filed a substantial number of patent applications covering various aspects of this technology. In the invention that is the subject matter of this specification, the Applicant has conceived a number of improvements and developments to the technology described in those patent applications.